Luigi formed Oball about 30 years ago and so this pieces was made in that time frame, probably more towards the beginning than the end. Some of his pieces had other names on them, but I can't pick out anything after Murano. He is seen as a master of the sommerso and has worked for and with some of the big names in glass.

To add to what David wrote, Luigi started making his own glass in 1978. Most of the pieces seen that have his name will be 1980s and later, so would be considered contemporary. The vase is not in the current Oball catalog, so it isn't brand new. Much of Oball's recent works have been three-layered sommerso or forms that differ from the classic shape your vase has. Because of this, I believe David is right that the vase is probably from the early years (80s-90s), though I wouldn't be able to zoom in.

After I wrote the last message, I realized that I haven't seen Luigi's signature on any of the more recent Oball pieces. I checked their company information at http://www.oball.com/company.html, so understand why. The Oball designs and production have been taken over by the two sons, Fabio and Michele.

Thanks for the additional information, both of you, and for helping pin the date down a little.

I had a look through the Oball website when I bought the vase - I do much prefer the (presumably) earlier, simpler pieces I've seen during my searches (it's the Scandinavian collector in me, I suspect).